Communications services companies sank amid a rush of earnings.

Twitter shares plunged more than 20% after the social-media company posted its slowest user growth in years and warned that uncertainty around the U.S. election could compress ad spending.

Facebook reported record revenue in the third quarter as strong digital-ad spending outweighed a high-profile ad boycott, data-gathering restrictions and continued fallout from the coronavirus pandemic. But looking past 2020, the company sounded less sanguine, and the stock fell 6.3% Friday.

Facebook finance chief David Wehner warned of a "significant amount of uncertainty" in the coming year.

Write to Amy Pessetto at amy.pessetto@dowjones.com

(END) Dow Jones Newswires

10-30-20 1739ET